Electric switching apparatus



May 17, 1932. c, H L 1,859,088

ELECTRIC SWITCHING APPARATUS Filed Dec. 51, 1927 2 Sheets-Sheet 1 I nmm.

InvenTor' Charles H. Hill, b3 HiSATTOPflC-EH.

May 17', 1932. c. H HELL 1,859,088

ELECTRIC SWITCHING APPARATUS Filed Dec. 31, 1927 2 Sheets-Sheet 2Invenl'or Charles PLHi H y MW Hi 5 ATTor'ne g- Patented May 17, 1932UNITED STATES PATENT OFFICE CHARLES H. I HILL, OF SCHENECTADY, NEW YORK,ASSIGNOR TO GENERAL ELECTRIC COMPANY, A GORPORATION OF NEW YORK ELECTRICSWITCHING APPARATUS Application filed December 31, 1927. Serial No.243,977.

My invention relates to electric switching apparatus and particularly toswitching apparatus of the character comprising a main switch unit whichis adapted to be removably mounted in a stationary frame and which hasdisconnecting switch terminals thereon which when the unit is raised andlowered in the frame cooperate with corresponding switch terminals onthe frame. The object of my invention is the provision of an improvedelectric switching apparatus having a construction which is sturdy,which facilitates convenience of handling and which is eflicient inoperation.

l\1y invention will be better understood from the following descriptiontaken in connection with the accompanying drawings,

and its scope will be pointed out in the appended claims. 7

Referring to the drawings, Fig. 1 is a perspective view of a switchingapparatus involving my invention; Fig. 2 is a side elevation thereofwith portions broken away; Figs. 3 and 4 are detail views and Fig. 5 isa sectional view on line 55 of Fig. 2.

In the drawings, the frame 1 of the apparatus is shown as fabricatedfrom structural steel members welded together and forming a supportingstructure for the main switch unit, the bus bars, the disconnectingswitch contracts, and the transformers, etc. associated therewith. Aplurality of similar apparatus may be arranged in a switching stationwith their frames standing side by side in a row either with their backsagainst a wall or otherwise or, if preferred, two such rows may bearranged with the apparatus placed back to back. In addition to themetal frame, the live portions of the apparatus are enclosed in metalliccasings from which they are separated in most parts by insulating oil orcompound hence the term metal clad tial transformers, connections 6being shown at the bottom of easing 4 for incoming or outgoing cablesdepending on the use of the apparatus. The connections between thecurrent transformers in casing 4 and the bus bars are enclosed by thecasing 7. Two flattened tubular casings 8 and 9 each enclose a group ofthree fixed disconnecting switch contacts 10 supported by rodsll, therods of one group of which connect by straps 12 with the respective busbars 3. The main switch unit comprising the oil switch 14, its operatingmechanism 15 and the movable contacts 16 of the disconnecting switch isremovably mounted in the frame and adapted frame. Internally the yokehas the guides" 21 on its two sides which are engaged by suitable lugsor projections on the oil switch. At the rear, the yoke is provided withlugs 22 and 23 having their adjacent faces inclined; The oil switch hasa projecting po'rtion'24 having correspondingly inclined faces whichwhen the switch is pushed rearwardly engage lugs 22 and 23 and firmlysecure the switch at the rear to the yoke. At the front the oil switchis secured to the yoke by the screws 25 which. pass through the plate 27forming a part of the switch into the ends of the yoke. By drawing up onthese screws 25 the switch is pushed rearwardly against the lugs 22 and23 and when thus engaged in the yoke the switch is firmly held againstsuch violent movements as might injure the disconnecting switchcontacts. In Fig. 3 the oil switch is shown removed and the yoke isshown in its lowermost position when it rests upon the angle 29. Afterthe oil switch has been IOU brought up to the frame by the carriage, itis slid into place in the yoke and the clamping screws 25 firmly secureit in the yoke. The switch and yoke are then raised together by suitablelifting means preferably mounted on the carriage in a well known mannerand which need not here be described. As the switch is raised,disconnecting switch contacts 16 and 10 engage the one within the otherwhereby the main or oil switch contacts are connected to the circuit.When the switch and the yoke have been raised the proper distance theyare locked in the raised position by the locking bars 30. Each bar has ahandle 31 and plates 32 which are adapt to slide in grooves 33 formed inthe guides 20. In the locking position the plates engage the lugs 19 andsupport the switch and yoke. As a result of this construction thelocking bars may be comparatively light and need be moved only enough toshift the plates from one position to the other. The bars may be securedin locking position by means such for example as a padlock 35 applied tothe members 36.

Inasmuch as the disconnecting switch contacts 10 and 16 are not daptedfor interrupting the circuit controlled by the oil switch 01' even forfinally closing the same, I have provided means for automaticallytripping open the oil switch and also for locking the switch operatingmechanism against movement to closed circuit position in the event thatone should begin to lower the oil switch when in closed circuitposition. Shaft 38 mounted in plate 27 of the oil switch has an arm 39carrying the roller 40 at its end which in the fully raised position ofthe switch engages in the notch 41 in fixed bar 42 forming a part of theframe. A. second arm 43 to which also the spring 44 is attached foryieldingly holding the roller against the bar 42 is connected throughlink 45, crank 46 and shaft 47 with arm 48 which moves the link 49 ofthe final holding toggle of the oil switch to trip the same to opencircuit position. This toggle also is adapted to be tripped in the usualand well known manner by the plunger 50 of the tripping coil 51. A thirdarm 53 on shaft 38 operates the locking member 54 which has the shoulder55 adapted to engage the shoulder 56 on the crank 57 of the switchoperating mechanism. The connection between arms 53 and 55 is shown ascomprising rod 60 on which is loosely mounted the block 61 between thenut 62 and the collar 63, a compression spring 64 normally holding theblock against the nut. Block 61 connects through crank 65 and shaft 66with locking member 54. Handle 67 is attached to shaft 38 on the frontof plate 27 whereby the tripping arm may be operated manually.

I have illustrated the main oil switch provided with a solenoid actuatedoperating mechanism of a well known construction comprising the mainoperating lever 68 which may be operated either by the solenoid or byhand and the adjustable link 69 connecting it to the crank 57 of theswitch. In the closing movement,- crank 57 is moved in a clockwisedirection as viewed Fig. 4. If the switch unit is in its fully raisedposition as illustrated in Fig. 4, the locking member will not interferewith this movement of crank 57 and the switch may be closed; If with theswitch closed one should start to lower the unit, the initial movementthereof would cause the roller 40 to ride out of the notch 41 andthrough tripping arm 48 immediatelytripthe switch to open circuitposition. At the same time locking member 54 is rotated counterclockwiseto such a position that its shoulder 55 lies in the path of shoulder 56on crank 57, thus positively locking the switch operating mechanismagainst movement to close the main switch. The locking member remains inthis position until the unit is returned to its fully raised positionwhen the roller will drop into the notch 41. In some cases it may bedesirable to close and open the oil switch when it is in the lowered ordisconnected position. I may therefore provide a second notch 41 toreceive roller 40 when the switch is in that position.

As shown in Fig. 1 the three bus bars 3 are enclosed in the bus chamberor trough 2. When a plurality of switching apparatus such as thatillustrated are arranged side by sidein a row, the respective bus barsand troughs are connected one with another to form a continuous lengthof trough with continuous bus bars therein. Each trough section isformed with flanges at the ends whereby the sections may be boltedtogether and the end of the bus bars have bolt holes by which the busconnecting plates 70 may be bolted thereto. The bus bars are supportedin proper position in the trough by the partitions 71 each shown ascomprising two layers or plates which are bolted along the periphery toan inwardly extending flange 7 2 on the trough. These partitions notonly support the bus bars but'serve to retain the insulating liquid '73in all of that portion of the trough between them. For making the jointstight between the partitions and the bus bars I have shown gaskets 74surrounding the bus bars and lying in recesses in the adjacent faces ofthe partitions. Gaskets may also be used if necessary between thepartitions and the flanges to which they are bolted. lhe top of thetrough is closed by a. cover plate 75 bolted to the- 1,s59,oss Y 3portions of the troughs, the main or body portions of the troughs beingundisturbed.

Referring now particularly to Fig. 5, it will seen that flattened metalcasings 8 and 9 each encloses a group of three fixed disconnectingswitch contacts 10 and each is supported by a flange on its upper endwhich is bolted to the frame. Within each casing are the threeinsulation tubes 7 8 each enclosing a contact 10 and its insulatedconnecting rod 11. Each rod and contact is supported by a member 7 9which is bolted to the flange of a casing and to which is bolted thetrough 2. In order that the heat produced .at the disconnecting switchcontacts may in all cases be dissipated with suflicient rapidity, I haveprovided a ventilating space between the insulating tubes 78 and fixedcontacts and parts associated therewith and in the bases of thesupporting member 79 have provided lateral openings 80 which communicatewith those spaces. Since the lower ends of the tubes 7 8 are neverentirely closed a cooling current of air is free to flow up past each ofthe disconnecting switch contacts and cool the same. What I claim as newand desire to secure by Letters Patent of the United States is:

1. Electrical switching apparatus comprising a frame, a U-shaped yokeguided for vertical movement within said frame, a main switch unitmounted within said yoke and detachably and rigidly secured thereto,said frame and switch unit having cooperating disconnecting switchcontacts, and means cooperating with the open end of said yokemaintaining said switch unit in position including a plate on whichswitch operating mechanism is mounted. w

2. Electric switching apparatus comprising a frame, a main switch unitsupported thereby and adapted to be raised and lowered therein, saidframe and switch unit having cooperating disconnecting switch contactsadapted to engage when the switch unit is in raised position, a yoke inwhich said switch unit is detachably secured, cooperating guides on theframe and the yoke and a locking bar slidably mounted engaging the yokeand frame for locking the yoke to the frame in its raised position.

3. Electric switching apparatus comprising a frame having fixeddisconnecting switch contacts, a main switch unit having cooperatingdisconnecting switch contacts adapted when the switch unit is raised toengage the fixed contacts, a yoke open at one side guided for verticalmovement in said frame, said unit being adapted to be inserted in andwithdrawn from the yoke through the open side thereof, means operablefrom said side for securely clamping the unit to the yoke againstrelative movement therein and locking bars engaging the yoke and framefor firmly securing the yoke to the frame in the raised position.

4. Electric switching apparatus comprising a frame, a main switch unitmounted to have vertical movement' therein, said framefor preventingswitch closing movement of I said mechanism upon movement of the unitfrom its uppermost position.

5. Electric switchingapparatus comprising a frame, a main switch unitmounted to have vertical movement therein and having an operatingmechanism and a tripping means carried thereby, said frame and switchunit having coopefiating disconnecting switch contacts separable by adownward movement of the unit, and means carried by the switch unit foroperating the tripping means and for preventing operation of theoperating mechanism upon the initial downward movement of the unit fromits upperm st position, said latter means including a controlling memberarranged to be actuated by engagement with a portion of said frame.

6. Electric switching apparatus comprising a frame, a main switch unitmounted to have vertical movement therein and having an operatingmechanism and a tripping means carried thereby, said frame and switchunit having cooperating disconnecting switch contacts separable by adownward movement of the unit, a locking member for preventing theoperating of the operating mechanism, a

member for operating the tripping means, and a device carried by saidunit and controlled by engagement with said frame for operating both ofsaid members in response to a lowering of said unit from a predeterminedraised position.

7 In electric switching apparatus, a fixed frame having downwardlyextending disconnecting switch contacts, a main switch unit havingcooperating disconnecting switch contacts and mounted for movement inthe frame to cause said contacts to be connected and,

disconnected, protective enclosing members for said contacts secured tothe frame and spaced from the c ntacts to provide ventilating passagesand contact supporting members secured to said frame having dischargeopenings communicating with said ventilating passages.

8. Electric switching appartus comprising afixed frame havingdisconnecting contacts thereon, a movable switch unit having coopcratingdisconnectlng contacts thereon, operating mechanism for the main switchunit mounted thereon and movable. therewith, said mechanism including atripping means and ameans for locking the mechanism in switch openposition, and a member engaging a portion of the fixed frame forcontrolllng the operation of said tripping and locldng means.

9. Electric switching apparatus comprising a fixed frame havingdisconnecting contacts thereon, a movable switch unit having cooperatingdisconnecting contacts thereon, operating mechanism for the main switchunit mounted thereon and movable therewith, said mechanism includingmeans for tripping open the main switch and for locking m the same inopen position, an' actuating arm for said means having a roller engaginga portion of the fixed frame, said portion having means thereon arrangedto operate the arm when the unit is moved from a prede- 15 tel-minedposition.

In witness whereof, I have hereunto set my hand this 30th dav ofDecember, 1927. CHARLES H. HILL.

